The most common solutions known in the art are devices which are provided with either one or several booms and by means of which only a stationary attachement between two hulls is usually achieved. The said booms are in a normal case on the same plane, and consequently, the movement of one hull is transmitted to the other hull in only a certain direction. The most conventional solutions in the art are those in which the booms are articulated to the hull via a horizontal axle journal, or ball joints can also be used.
As is evident from the above, the devices known in the art have the disadvantage that by means of them it is possible to coordinate the movements between two hulls to each other to a very limited degree, usually in only one direction. It can also be regarded as a disadvantage in the said devices that by means of them it is not possible to adjust the draught between the hulls in any way, and neither is it possible to steer one hull by means of the other.